This is the story of an MA-40 rotatable crank-up antenna tower in Cupertino, CA, in the heart of Silicon Valley.
Ham towers are a longstanding tradition here so city permit staff didn't even bat an eye, although if I'd gone above 55' they might have wanted to have a conversation.
US Tower is also in California, so our local building department was happy with their engineering stamp too. And so it began...
June 2010: the foundation

The city originally approved a 55' MA-550. I later decided to downsize to the 40' MA-40, but it seemed best to pour the foundation per the original plans: 3.5' wide by 5' deep, which is a half-foot more in each direction than required for an MA-40.
Since we happened to be building a house to accompany the new tower, I had the same concrete company pour the basement and the tower foundation at the same time. Notice the professional rebar work, with a square inside another square.

In the photo below, you can see a ground wire in the middle of the cage. It connects the bolts and rebar to a nearby ground rod, which is in turn connected to all other grounding points around the home. The tower's bolts are held in place at the top by a wooden pattern provided by US Tower.

US Tower sent the bolts and pattern before the tower arrived, so we could get the foundation poured and dried first. The 3/4" thick MA-40 bolts were the only items changed from the original 1" MA-550 foundation plans.
The foundation required about 5 yards of concrete. The ground will be built up around this when it's landscaping time. The gray PVC pipes are conduits running from the house for underground coax and control cables.

Work of art, huh?

tower installation » antenna installation »» final installation »»»
Other projects:
Antenna Farm 3: The Slanted Roof Solution
Antenna Farm 2: The Flat Roof Challenge
Flagpole Antenna Project • Antenna Farm 1
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